Piedinature - Pinouts
Commodore C16/+4 Expansion Bus

Reference and Sources:

Available on Commodore C16, C116 and +4 computers.

50 PIN FEMALE EDGE (2 mm pitch) at the Computer.

Pin	Name	Description
1	GND	Ground
2	+5V	+5 VDC
3	+5V	+5 VDC
4	/IRQ	Interrupt
5	R/W	Read/Write (1=Read, 0=Write)
6	C1HIGH	External Cartridge Chip Selects C1 High
7	C2LOW	External Cartridge Chip Selects C2 Low (reserved)
8	C2HIGH	External Cartridge Chip Selects C2 High (reserved)
9	/CS1	Chip Select Line 1
10	/CS0	Chip Select Line 0
11	/CAS	Column Address Strobe
12	MUX	DRAM address multiplex control signal
13	BA	Bus Available (Low=DMA)
14	D7	Data 7
15	D6	Data 6
16	D5	Data 5
17	D4	Data 4
18	D3	Data 3
19	D2	Data 2
20	D1	Data 1
21	D0	Data 0
22	AEC	Address Enable Code
23	EAI	External Audio In
24	PHI 2	Artificial Phi 2 signal
25	GND	Ground
A	GND	Ground
B	C1LOW	External Cartridge Chip Selects C1 Low
C	/RESET	Reset
D	/RAS	Row Address Strobe
E	PHI 0	Artificial Phi 0 Signal
F	A15	Address 15
H	A14	Address 14
J	A13	Address 13
K	A12	Address 12
L	A11	Address 11
M	A10	Address 10
N	A9	Address 9
P	A8	Address 8
R	A7	Address 7
S	A6	Address 6
T	A5	Address 5
U	A4	Address 4
V	A3	Address 3
W	A2	Address 2
X	A1	Address 1
Y	A0	Address 0
Z	n/c	Not connected
AA	n/c	Not connected
BB	n/c	Not connected
CC	GND	Ground

PHI 2: Address valid on the rising edge, data valid on the falling edge

Piedinature - PinoutsCommodore C16/+4 Expansion Bus